1. Field of the Invention
The present invention relates to a production method for an IC card having a semiconductor module embedded in a card board, and to the IC card.
1. Description of the Prior Art
Conventionally, there are known IC cards having semiconductor modules embedded in concaves of a card board and glued thereto. Explanation follows below of an IC card of this kind with reference to FIG. 9a and FIG. 9b.
FIG. 9a shows a plan view of a conventional IC card, and FIG. 9b shows a cross-sectional view taken along the line IX--IX in FIG. 9a. In these figures, a semiconductor module 2 (hereinafter merely referred to as "module") is fastened onto a card board 1. Card board 1 is made by stratifying vinyl chloride resin sheets or by molding of ABS resin or the like, and thereby a concave 1a, onto which the module 2 is embedded, is formed. Concave 1a is formed with its opening facing upward of the card board 1. Module Z consists of a board 4 mounted with a semiconductor element 3, a thin wire 5 electrically connected between a wiring circuit (not illustrated here) of the board 4 and the semiconductor element 3, and a sealed resin 6 which seals semiconductor element 3, thin wire 5, and the like. An electrode terminal 7 for external connection to the IC card is formed on a surface of board 4 and is opposite to the surface on which a semiconductor element is mounted.
The module 2 is formed in such a size that the board 4 and sealed resin 6 are embedded in the concave 1a of the card board 1, and side and bottom faces are respectively made flat.
In the conventional IC card thus structured, assembling is carried out by embedding the module 2 into the concave 1a in such condition that the module 2 or the concave 1a of the card board 1 is applied with adhesive. When assembling the module, a side of sealed resin 6 is first embedded into the concave 1a, so that the electrode terminal 7 can be exposed to the level of an upper surface of the card board.
However, with the conventional IC card production method in which a module 2 is thus embedded into the concave 1a of the card board 1, in order to firmly fasten the module 2 onto the card board 1, it is necessary that the shape of concave 1a be in agreement with that of the module 2, or the shape of the module 2 be in agreement with that of the concave 1a. Unless the shape of those two are in agreement with each other, irregular steps are naturally generated on the surface of IC card. Besides, it is necessary to carry out firm fastening so that the module 2 should not drop from the IC card. Furthermore, it is stipulated in JIS or ISO Standards that there should not be any irregularity or steps of more than 0.1 mm between an electrode terminal and its peripheral card surface. These are some of the various problems that require many processes and necessitate handling of the adhesive which may stain the card surface when the shape of the concave 1a and the shape of module 2 must be made to precisely conform, and when the adhesive must be properly placed therebetween.